A TM ₀ mode coupled travelling wave SNSPD based on SOI platform is designed. The light propagating in this device can achieve high-efficiency mode conversion from TE ₀ mode to TM ₀ mode and then absorbed by NbN nanowires on top of the waveguide. Thanks to the TM ₀ mode coupled detection, the length of NbN nanowire that is needed to achieve a close-to-unity photon absorption is cut down to an extremely short level of ∼5 μm. Meanwhile, this TM ₀ mode coupled travelling wave SNSPD is very robust against fabrication errors compared with TE ₀ coupled SNSPD.

中文翻译：

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基于TM ₀模式吸收的耐制造紧凑型波导超导单光子探测器设计

设计了一种基于SOI平台的TM ₀模耦合行波SNSPD。在该器件中传播的光可以实现从 TE ₀模式到 TM ₀模式的高效模式转换 ，然后被波导顶部的 NbN 纳米线吸收。由于TM ₀模式耦合检测，实现接近统一的光子吸收所需的NbN 纳米线的长度被减少到~5 μm 的极短水平。同时，与TE ₀耦合SNSPD相比，这种TM ₀模式耦合行波SNSPD 对制造误差非常稳健 。